cosi 227: advanced topics in database systems
DESCRIPTION
COSI 227: Advanced Topics in Database Systems. Mitch Cherniack Spring, 2003 Tuesdays: 1:40-4:30 Volen 106 (until further notice). COSI 227 Syllabus. Stream Data Management: A Teaser. Application: Battlefield Monitoring. Future of battle gear: 100’s of sensors! GPS - PowerPoint PPT PresentationTRANSCRIPT
COSI 227: Advanced Topics in Database Systems
Mitch Cherniack
Spring, 2003Tuesdays: 1:40-4:30
Volen 106 (until further notice)
Application: Battlefield Monitoring
Future of battle gear: 100’s of sensors! GPS Vital signs (pulse, pressure, breathing) Dehydration (pill sensors!) …
Battalions: ~ 30K Soldiers O (106) streams of sensor readings
Application: Battlefield Monitoring
What To Do With Sensor Data? Filter, Analyze, Correlate (I.e., Query!)
Center-of-Mass Crossing-the-border Remote triage Enemy Attack Alert Fratricide Alert Front line
Why Do DB People Care?
Need for Data Management Constrained resources (bandwidth, CPU, disk,…) Numerous data sources (O (106) sensors) Numerous queries (O (103) simultaneous queries)
Queries! Remote triage? Selection! Center-of-mass? Aggregation! Fratricide Alerts? Joins!
Databases Turned On Their Ear
Traditional: data static/query transient Streams: query static/data transient
Traditional: pull-based (finite) data Streams: push-based (infinite) data
Traditional: need to index data Streams: need to index queries
Traditional: Best-effort service Streams: Real-time
Other Stream Applications
Position Tracking (OZ Entertainment) Highway/Air Traffic Control Habitat Monitoring Physical Plant Monitoring Outpatient Monitoring Financial Trading Credit Card Fraud Detection Network Monitoring (e.g., DoS Attacks) …
Much DB/OS Work to Draw On…
Persistent Queries: Triggers (active databases) Views Publish/Subscribe (e.g., portals)
Streaming Data: Temporal Databases Sequence Databases
Real-Time: Real-time Databases Quality-Of-Service (QoS) Load Shedding, Scheduling
Major Projects in the Area…
STREAM (Stanford) Telegraph (UC Berkeley) Niagara (Wisconsin, OGI) Cougar (Cornell) Aurora (Brandeis, Brown, MIT)
Reading List
Complete list available next class Next week: Pervasive Computing
The Computer for the 21st Century, Weiser Challenges in Ubiquitous Data Management,
Franklin Profile-Driven Cache Management:
Cherniack, Galvez, Franklin, and Zdonik
Your Homework 3 Readings + 3 Summaries Choose 5 dates/topics for presentations
Characteristics of Research Papers
Condensed Style Page Limits Target Audience: Researchers in Field Intended message Message you
seek…
Reading as a novice Seek supplementary readings “Active Reading” Multiple, targeted readings
Types of Research Papers
Conference Papers Strict Page Limits (10-12 pages) Peer-reviewed (I.e., some quality control) Most visible venue for Systems Research Most Important: SIGMOD, VLDB, ICDE, PODS
Journal Papers No (or very generous) page limits Peer-reviewed Expanded version of 1+ conference papers Most Important: TODS, VLDB Journal, JACM*
Types of Research Papers (cont.)
Workshop Papers Strict Page Limits (10-12 pages) Peer-reviewed Designed to present early work (feedback-
oriented) Examples: WebDB, HotOS, CIDR (not WIDR)
Technical Reports Internal (Department) Publications No Page Limits Not peer-reviewed Best source of details
Active Reading
Questions to ask as you read…
1. What are the motivations for this work?
2. What is the proposed solution?
3. What is the evaluation methodology?
4. What are the contributions?
Active Reading
Multiple readings 1st reading:
Understand: motivation, contributions High-Level Understanding: solution,
evaluation criteria Main Foci: Introduction, Related Work,
Conclusions 2nd, 3rd readings:
Deep understanding of solution, evaluation…
Active Reading
Deep Understanding of Solution If an algorithm: trace on examples If an architecture: trace execution “Paper-and-pencil” reading
Deep Understanding of Evaluation If a key proof: trace the steps of the
proof If empirical: look for anomalies and
explanations for them…
If You’re A Presenter…
Look for background material… Accompanying technical report Follow-up journal paper Survey on the area (ACM Computing Surveys) Related Work (paper bibliography+) Tutorial on the area
Indexes are your friend… DBLP (http://www.informatik.uni-trier.de/~ley/db/) Citeseer (http://citeseer.nj.nec.com/cs) ACM Digital Libraries (link from http://www.library.
brandeis.edu/resources/dbs/computer.html) Google
How to give a good research talk
Adapted from a talk bySimon Peyton JonesMicrosoft Research
See http://research.microsoft.com/Users/simonpj/papers/giving-a-talk.htm
Do it! Do it! Do it!
Good talks are a fundamental part of research excellence
Invest time
Learn skills
Practice
Giving a good talk
This presentation is about how to give a good research talk
What your talk is for
What to put in it (and what not to)
How to present it
The purpose of your talk…
..is not:
To impress your audience with your brainpower
To tell them all you know about your topic
To present all the technical details
The purpose of your talk…
..but is:
To give your audience an intuitive feel for an idea
To make them foam at the mouth with eagerness to (re)read the paper
To engage, excite, provoke them
Your audience…
The audience you would like…
Will have read the paper as many times as you
Will have read all background papers
Thoroughly understand all the relevant theory of cartesian closed endomorphic bifunctors
Are all agog to hear your interpretation of the paper
Are fresh, alert, and ready for action
Your actual audience…
The audience you get…
Have read the paper once
Will not have read background material
Have heard of bifunctors, but wish they hadn’t
Have just had lunch and are ready for a dozeYour mission is to
WAKE THEM UPAnd make them glad they did
Outlines as Milestone Markers
Rule-of-thumb (presenting, papers, teaching…)
Tell them what you’re going to do
Do it
Tell them what you did
Variations on a themeRemind them what you’ve done so far
Remind them what you’ve yet to do
Motivation
You have 2 minutes to engage your audience before they start to doze
Why should I tune into this talk?
What is the problem?
Why is it an interesting problem?
Give an example! (e.g. Battlefield monitoring)
The key idea
If the audience remembers only one thing from your talk, what should it be?
You must identify the key idea. “Talked about Query Optimization” is No Good.
Be specific. Don’t leave your audience to figure it out for themselves.
Be absolutely specific. Say “If you remember nothing else, remember this.”
Organize your talk around this specific goal. Ruthlessly prune material that is irrelevant to this goal.
Your main weapon
Examples are your main weapon
To motivate the work To convey the basic intuition To illustrate The Idea in action To show extreme cases To highlight shortcomings
When time is short, omit the general case, not the example
Slides You Don’t Understand
Don’t BS! (It is far more transparent than you think)
Getting Caught is Embarassing! It is OK not to understand some details
You should demonstrate your effort to understand (I tried to understand X with the following example but got different results)
You can use this as an opportunity to engage the class…
… but don’t do this too often!
Omit gory details
Even though you spent hours understanding the details, dense clouds of notation will send your audience to sleep
Present specific aspects only that are relevant to examplesor ideas
Note: Leaving it out doesn’t mean you don’t need to understand it!
Unnecessary Verbiage
Slides that have a lot of text on them put audiences to sleep. Try to avoid writing a “brain dump” on your slide. Your audience will end up reading the slide instead of listening to you (and that’s if you’re lucky) and will quickly lose interest in the talk. Worse, this practice tends to make speakers “read their slides”. YAWN!!!!. Instead…
2 Weeks Before Presenting…
Read the papers your group will present Think About How to Integrate the Ideas in
Various Papers Meet with your Groupmates:
Plan the class. E.g. 1:40-1:55 - Introduction, Plan for Class 1:55-2:40 – Paper #1 2:40-3:25 – Paper #2 3:25-3:30 – Break 3:30-4:00 - Paper #3 4:00-4:30 - Discussion, Integration
Divide the Work (but plan to keep in touch!)
1 Week Before Presenting…
Meet with me with a draft of your slides and timeline (failure to do so = penalty)
Edit slides and timeline Practice, practice, practice!
An Hour Before Presenting…
Many people experience apparently-severe pre-talk symptoms
Inability to breathe Inability to stand up (legs give way) Inability to operate brain
What to do about it
Deep breathing during previous talk
Script your first few sentences precisely (=> no brain required)
Move around a lot, use large gestures, wave your arms, stand on chairs
Go to the bathroom first
You are not a wimp. Everyone feels this way.
Enthusiasm
If you do not seem excited by your idea, why should the audience be?
It wakes ‘em up
Enthusiasm makes people dramatically more receptive
It gets you loosened up, breathing, moving around
Being seen, being heard
Point at the screen, not at the overhead projector
Speak to someone at the back of the room, even if you have a microphone on
Make eye contact; identify a nodder, and speak to him or her (better still, more than one)
Watch audience for questions… (I ask my share…)
Questions
Questions are not a problem
Questions are a golden golden golden opportunity to connect with your audience
Specifically encourage questions during your talk: pause briefly now and then, ask for questions
Be prepared to truncate your talk if you run out of time. Better to connect, and not to present all your material
Keep To your Timeline!
Absolutely without fail, finish on time
Audiences get restive and essentially stop listening when your time is up. Continuing is very counter productive
Simply truncate and conclude
Learn From Others
Watch and learn!Critique your classmates as to how well they follow these guidelines
See visiting speakers also! (You’ll be amazed by how many “big shots” can’t give a good talk)
NEDS: One Friday Per Month3-4: Wine and Cheese with the Speaker
4-5: Talk (Must attend if you imbibe from 3-4)Next meeting: January 17